Communication apparatus, base station, and communication method for non-cell defining SSB

The present application is a continuation application of international Patent Application No. PCT/JP2022/040010, filed on Oct. 26, 2022, which designated the U.S., and claims the benefit of priority of Japanese Patent Application No. 2021-179813, filed on Nov. 2, 2021, the entire contents of which are incorporated herein by reference.

The present disclosure relates to a communication apparatus, a base station, and a communication method used in a mobile communication system.

In recent years, in the 3rd generation partnership project (3GPP) (registered trademark, the same applies hereinafter), which is a standardization project of a mobile communication system, it has been studied to provide a specific user equipment having a lower communication capability than that of general user equipment in the fifth generation (5G) system. The specific user equipment is a user equipment having middle range performance and price for Internet of Things (IoT), and for example, a maximum bandwidth used for radio communication is set narrower or the number of receivers is smaller as compared with the general user equipment. Such a specific user equipment is referred to as reduced capability user equipment (RedCap UE).

In addition, in the 5G system, a bandwidth part (BWP) is defined in order to reduce power consumption of the user equipment and effectively use a broadband carrier (see, for example, Non Patent Literature 1). The user equipment configured with the BWP does not need to support the same bandwidth as a bandwidth of a cell, and can perform communication in a frequency band narrower than the bandwidth of the cell. The BWP includes an initial BWP (an initial DL BWP and an initial UL BWP) and a dedicated BWP (a dedicated DL BWP and a dedicated UL BWP). Here, DL refers to downlink and UL refers to downlink. The initial BWP is at least a BWP used for initial access, and is commonly used for a plurality of user equipments. The dedicated BWP is a BWP configured to be dedicated to a certain user equipment (UE-specific BWP).

A base station transmits a synchronization signal block (synchronization signal/physical broadcast channel (PBCH) block (SSB)) in the initial BWP (initial DL BWP). The synchronization signal block may be referred to as a synchronization signal/physical broadcast channel block. An SSB associated with a system information block type 1 (SIB1) is referred to as a cell defining SSB (CD-SSB). From the perspective of one UE, one serving cell is associated with one CD-SSB. The SIB1 is also referred to as remaining minimum system information (RMSI). For example, the user equipment performs cell search and cell selection/reselection based on the received CD-SSB.

In the 3GPP, assuming the RedCap UE, it is agreed to configure an initial BWP for the RedCap UE independently of the conventional initial BWP. Such a newly introduced initial BWP is referred to as a separate initial BWP. In addition, it is proposed to configure SSB transmission in the separate initial DL BWP (see, for example, Non Patent Literatures 2 and 3).

Meanwhile, a spatial setting is configured from the base station to the user equipment for the purpose of beam control of a physical uplink control channel (PUCCH) for transmitting uplink control information (UCI) from the user equipment to the base station. Such a spatial setting includes a parameter for configuring a signal to be referred to in the beam control of the PUCCH, and an SSB index can be configured as the parameter (see, for example, Non Patent Literature 4). The user equipment configured with the SSB index as the spatial setting for the PUCCH transmission performs the PUCCH transmission using the same spatial domain filter as a spatial domain filter used for reception of an SSB indicated by the SSB index (see, for example, Non Patent Literature 5).

Non Patent Literature 1: 3GPP technical specification “TS 38.300 V16.7.0” Non Patent Literature 2: 3GPP Contribution “R1-2106563” Non Patent Literature 3: 3GPP Contribution “R1-2106601” Non Patent Literature 4: 3GPP technical specification “TS 38.331 V16.6.0” Non Patent Literature 5: 3GPP technical specification “TS 38.213 V16.7.0”

100 112 200 120 120 502 A communication apparatus () according to a first feature includes: a receiver () configured to receive, from a base station (), configuration information including a synchronization signal/physical broadcast channel block (SSB) index indicating an SSB to be referred to for performing at least one of operations of radio link monitoring (RLM) and beam failure detection (BFD); and a controller () configured to perform the at least one operation with reference to the SSB indicated by the SSB index. The controller () is configured to specify the SSB indicated by the SSB index as a non-cell-defining SSB () in a case where an absolute radio-frequency channel number indicating a frequency location at which the non-cell-defining SSB is transmitted is received.

200 211 100 211 100 502 A base station () according to a second feature includes: a transmitter () configured to transmit, to a communication apparatus (), configuration information including a synchronization signal/physical broadcast channel block (SSB) index indicating an SSB to be referred to for performing at least one of operations of radio link monitoring (RLM) and beam failure detection (BFD). The transmitter () is configured to transmit, to the communication apparatus (), an absolute radio-frequency channel number for specifying the SSB indicated by the SSB index as a non-cell-defining SSB (), the absolute radio-frequency channel number indicating a frequency location at which the non-cell-defining SSB is transmitted.

100 200 502 A communication method according to a third feature is executed by a communication apparatus (). The communication method includes the steps of: receiving, from a base station (), configuration information including a synchronization signal/physical broadcast channel block (SSB) index indicating an SSB to be referred to for performing at least one of operations of radio link monitoring (RLM) and beam failure detection (BFD); and performing the at least one operation with reference to the SSB indicated by the SSB index. The performing of the at least one operation includes specifying the SSB indicated by the SSB index as a non-cell-defining SSB () in a case where an absolute radio-frequency channel number indicating a frequency location at which the non-cell-defining SSB is transmitted is received.

200 100 100 502 A communication method according to a fourth feature is executed by a base station (). The communication method includes the steps of: transmitting, to a communication apparatus (), configuration information including a synchronization signal/physical broadcast channel block (SSB) index indicating an SSB to be referred to for performing at least one of operations of radio link monitoring (RLM) and beam failure detection (BFD); and transmitting, to the communication apparatus (), an absolute radio-frequency channel number for specifying the SSB indicated by the SSB index as a non-cell-defining SSB (), the absolute radio-frequency channel number indicating a frequency location at which the non-cell-defining SSB is transmitted.

One or more embodiments of a mobile communication system will now be described with reference to the accompanying figures. Like elements in the various figures are denoted by like reference numerals.

In a case where one cell of a base station is configured with a separate initial bandwidth part (BWP) in addition to a conventional initial BWP, it is conceivable that the base station transmits a cell defining synchronization signal/physical broadcast channel (PBCH) block (CD-SSB) in the conventional initial DL BWP and transmits a non-cell-defining SSB (Non-CD-SSB) in the separate initial DL BWP.

In an existing 3GPP technical specification, in a case where an SSB is used for beam control of a physical uplink control channel (PUCCH), an SSB index is configured for a user equipment on the assumption that there is only one SSB in a serving cell. There is no problem if only one SSB is transmitted in the serving cell. However, there is a problem that the user equipment cannot know which SSB should be used for the beam control of the PUCCH when the Non-CD-SSB is transmitted in the cell in addition to the CD-SSB.

Therefore, an object of the present disclosure is to provide a user equipment, a base station, and a communication method capable of appropriately controlling PUCCH transmission even in a case where a Non-CD-SSB is transmitted in a cell in addition to a CD-SSB.

(Configuration of Mobile Communication System)

1 1 1 1 FIG. A configuration of a mobile communication systemaccording to the embodiment will be described with reference to. The mobile communication systemis, for example, a system conforming to a technical specification (TS) of the 3rd generation partnership project (3GPP). Hereinafter, as the mobile communication system, a description will be given, as an example, as to the 5th generation system (5GS) of the 3GPP standard, that is, a mobile communication system based on new radio (NR).

1 10 100 10 10 20 30 The mobile communication systemincludes a networkand a user equipment (UE)that communicates with the network. The networkincludes a next generation radio access network (NG-RAN), which is a 5G radio access network, and a 5G core network (5GC), which is a 5G core network.

100 200 100 100 100 100 100 100 The UEis a communication apparatus that communicates with a base station. The UEis an apparatus used by a user. The UEis, for example, a mobile apparatus such as a mobile phone terminal such as a smartphone, a tablet terminal, a notebook personal computer (PC), a communication module, or a communication card. The UEmay be a vehicle (for example, a car or a train) or an apparatus provided in the vehicle. The UEmay be a transport body other than a vehicle (for example, a ship or an airplane) or an apparatus provided in the transport body. The UEmay be a sensor or an apparatus provided in the sensor. Note that the UEmay be referred to as another name such as a mobile station, a mobile terminal, a mobile apparatus, a mobile unit, a subscriber station, a subscriber terminal, a subscriber apparatus, a subscriber unit, a wireless station, a wireless terminal, a wireless apparatus, a wireless unit, a remote station, a remote terminal, a remote apparatus, or a remote unit.

100 100 100 100 100 100 100 100 In the present embodiment, as the UEof NR, two types of UEs are assumed, that is, a general user equipment (Non-RedCap UE)A and a specific user equipment (RedCap UE)B having a lower communication capability than that of the general UEA. The general UEA has an advanced communication capability such as a high speed and high capacity (enhanced mobile broadband: eMBB) and ultra-reliable low delay (ultra-reliable and low latency communications: URLLC), which are characteristics of NR. Therefore, the general UEA has a higher communication capability than the specific UEB. The general UEA may be an existing UE, that is, a UE prior to Release 16 of the 3GPP technical specification (so-called legacy UE).

100 100 100 100 100 100 100 100 100 The specific UEB is a UE whose apparatus cost and complexity are reduced as compared with the general UEA. The specific UEB is a UEhaving middle range performance and price for Internet of Things (IoT), and for example, a maximum bandwidth used for radio communication is set narrower or the number of receivers is smaller as compared with the general UEA. Note that the receiver may be referred to as a reception branch. The specific UEB may be referred to as a reduced capability NR device. Hereinafter, when the general UEA and the specific UEB are not distinguished, they are simply referred to as the UE.

100 100 100 100 100 100 100 The specific UEB may be able to communicate at a communication speed equal to or higher than a communication speed specified in a low power wide area (LPWA) standard, for example, long term evolution (LTE) Cat.1/1 bis, LTE Cat.M1 (LTE-M), or LTE Cat.NB1 (NB-IoT). The specific UEB may be capable of communicating with a bandwidth equal to or larger than a bandwidth defined by the LPWA standard. The specific UEB may support a limited bandwidth used for communication as compared with a UE of Release 15 or Release 16 of the 3GPP technical specification. For example, regarding a frequency range 1 (FR1), the maximum bandwidth (also referred to as a UE maximum bandwidth) supported by the specific UEB may be 20 MHz. In addition, regarding a frequency range 2 (FR2), the maximum bandwidth supported by the specific UEB may be 100 MHz. The specific UEB may have only one receiver that receives a radio signal. The specific UEB may be, for example, a wearable apparatus, a sensor apparatus, or the like.

20 200 200 100 200 100 200 100 200 100 30 200 The NG-RANincludes a plurality of base stations. Each of the base stationsmanages at least one cell. A cell forms a minimum unit of a communication area. For example, one cell belongs to one frequency (a carrier frequency) and is formed by one component carrier. The term “cell” may represent a radio communication resource, and may also represent a communication target of the UE. Each base stationcan perform radio communication with the UEexisting in its own cell. The base stationcommunicates with the UEby using a protocol stack of the RAN. The base stationprovides NR user plane and control plane protocol terminations towards the UEand is connected to the 5GCvia an NG interface. Such an NR base stationmay be referred to as a gNodeB (gNB).

30 300 300 100 200 The 5GCincludes a core network apparatus. The core network apparatusincludes, for example, an access and mobility management function (AMF) and/or a user plane function (UPF). The AMF performs mobility management of the UE. The UPF provides a function specialized for user plane processing. The AMF and the UPF are connected to the base stationvia the NG interface.

1 2 FIG. Next, a configuration example of a protocol stack in the mobile communication systemaccording to one or more embodiments will be described with reference to.

100 200 A protocol of a radio section between the UEand the base stationincludes a physical (PHY) layer, a medium access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, and a radio resource control (RRC) layer.

100 200 The PHY layer performs encoding and decoding, modulation and demodulation, antenna mapping and demapping, and resource mapping and demapping. Data and control information are transmitted between the PHY layer of the UEand the PHY layer of the base stationvia a physical channel.

The physical channel includes a plurality of orthogonal frequency division multiplexing (OFDM) symbols in the time domain and a plurality of subcarriers in the frequency domain. One subframe includes a plurality of OFDM symbols in the time domain. A resource block (RB) is a resource allocation unit, and includes a plurality of OFDM symbols and a plurality of subcarriers. Specifically, in the 5G system, downlink transmission and uplink transmission are configured in a radio frame of 10 ms duration.

For example, the radio frame includes 10 subframes. For example, one subframe may be 1 ms. Furthermore, one subframe may include one or more slots. For example, the number of symbols forming one slot is normally 14 for a cyclic prefix (CP) and 12 for an extended CP. In addition, the number of slots forming one subframe changes according to the configured subcarrier spacing. For example, for the normal CP, when 15 kHz is configured as the subcarrier spacing, the number of slots per subframe is 1 (that is, 14 symbols), when 30 kHz is configured as the subcarrier spacing, the number of slots per subframe is 2 (that is, 28 symbols), when 60 kHz is configured as the subcarrier spacing, the number of slots per subframe is 4 (that is, 56 symbols), and when 120 kHz is configured as the subcarrier spacing, the number of slots per subframe is 8 (that is, 128 symbols). In addition, for the extended CP, when 60 kHz is configured as the subcarrier spacing, the number of slots per subframe is 4 (that is, 48 symbols).

100 200 100 200 Among the physical channels, a physical downlink control channel (PDCCH) plays a central role for purposes such as, for example, downlink scheduling allocation, uplink scheduling grant, and transmission power control. For example, the UEperforms blind decoding of the PDCCH using a cell-radio network temporary identifier (C-RNTI) and a modulation and coding scheme-C-RNTI (MCS-C-RNTI) or a configured scheduling-RNTI (CS-RNTI) allocated from the base stationto the UE, and acquires a downlink control information (DCI) which has been successfully decoded as a DCI addressed to its own UE. Here, a cyclic redundancy check (CRC) parity bit scrambled by the C-RNTI and the MCS-C-RNTI or the CS-RNTI is added to the DCI transmitted from the base station.

100 200 100 100 100 200 200 100 The UEcan use a bandwidth narrower than a system bandwidth (that is, the bandwidth of the cell). The base stationconfigures a bandwidth part (BWP) of consecutive PRBs for the UE. The UEtransmits and receives data and a control signal in an active BWP. The BWPs may have different subcarrier spacings or may have frequencies overlapping each other. In a case where a plurality of BWPs are configured for the UE, the base stationcan designate which BWP is to be activated by control in downlink. As a result, the base stationcan dynamically adjust a UE bandwidth according to the amount of data traffic of the UEand the like, and can reduce the UE power consumption.

200 100 100 The base stationmay configure, for example, a maximum of three control resource sets (CORESETs) for each of a maximum of four BWPs on a serving cell. The CORESET is a radio resource for control information to be received by the UE. A maximum of 12 CORESETs may be configured on the serving cell for the UE. Each CORESET has an index of 0 to 11. For example, the CORESET includes six resource blocks (PRB) and one, two, or three consecutive OFDM symbols in the time domain.

100 200 200 100 The MAC layer performs priority control of data, retransmission processing by a hybrid automatic repeat request (HARQ: Hybrid Automatic Repeat reQuest), a random access procedure, and the like. Data and control information are transmitted between the MAC layer of the UEand the MAC layer of the base stationvia a transport channel. The MAC layer of the base stationincludes a scheduler. The scheduler determines uplink and downlink transport formats (transport block size and modulation and coding scheme (MCS)) and resources to be allocated to the UE.

100 200 The RLC layer transmits data to the RLC layer on a reception side using the functions of the MAC layer and the PHY layer. Data and control information are transmitted between the RLC layer of the UEand the RLC layer of the base stationvia a logical channel.

The PDCP layer performs header compression and decompression and encryption and decryption.

A service data adaptation protocol (SDAP) layer may be provided as an upper layer of the PDCP layer. The service data adaptation protocol (SDAP) layer performs mapping between an IP flow that is a unit in which a core network performs quality of service (QoS) control, and a radio bearer that is a unit in which an access stratum (AS) performs QoS control.

100 200 100 200 100 100 200 100 100 200 100 The RRC layer controls the logical channel, the transport channel, and the physical channel according to establishment, reestablishment, and release of the radio bearer. RRC signaling for various configurations is transmitted between the RRC layer of the UEand the RRC layer of the base station. In a case where there is an RRC connection between the RRC of the UEand the RRC of the base station, the UEis in an RRC connected state. In a case where there is no RRC connection between the RRC of the UEand the RRC of the base station, the UEis in an RRC idle state. In a case where an RRC connection between the RRC of the UEand the RRC of the base stationis suspended, the UEis in an RRC inactive state.

100 100 300 100 A non-access stratum (NAS) layer located above the RRC layer performs session management and mobility management of the UE. NAS signaling is transmitted between the NAS layer of the UEand the NAS layer of the core network apparatus(AMF). Note that the UEhas an application layer and the like in addition to a protocol of a radio interface.

(BWP)

100 100 A BWP is defined for reducing power consumption of the UEand effectively using a broadband carrier. The BWP includes an initial BWP (an initial DL BWP and an initial UL BWP) and a dedicated BWP (a dedicated DL BWP and a dedicated UL BWP). Up to four DL BWPs and up to four UL BWPs are configured in one serving cell for the UEaccording to the capability. In the following description, when the DL BWP and the UL BWP are not distinguished, they are simply referred to as the BWP.

100 The initial BWP is at least a BWP used for initial access, and is commonly used by a plurality of UEs. bwp-id, which is a BWP identifier, is defined as “0” for each of the initial DL BWP and the initial UL BWP. There are two types of initial BWPs: an initial BWP derived and configured by a master information block (MIB) transmitted on a PBCH; and an initial BWP configured by a system information block (SIB), specifically, a system information block type 1 (SIB1). The initial BWP configured by the MIB has a bandwidth corresponding to CORESET #0 configured using parameters included in the MIB. The initial BWP configured by the SIB1 is configured by various parameters (locationAndBandwidth, subcarrierSpacing, and cyclicPrefix) included in ServingCellConfigCommonSIB which is an information element in the SIB1.

100 100 100 100 100 Upon initial access to a cell, the UEthat has received an SSB of the cell acquires a bandwidth (24, 48, or 96 RBs) of a Type-0 PDCCH CSS set from a setting value of controlResourceSetZero (an integer value from 0 to 15) in pdcch-ConfigSIB1 which is an information element included in the PBCH (MIB). Then, the UEmonitors the Type-0 PDCCH CSS set to acquire the SIB1, and acquires locationAndBandwidth, which is a parameter indicating a frequency location and/or bandwidth of the initial BWP, from the SIB1. The UEuses the initial BWP configured by the MIB, that is, the bandwidth based on CORESET #0, as the initial BWP until a message 4 (Msg. 4) during a random access procedure in the initial access is received. On the other hand, after the Msg.4 is received, the UEuses the bandwidth configured by locationAndBandwidth in the SIB1 as the initial BWP. Note that Msg.4 may be an RRCSetup message, an RRCResume message, or an RRCReestablishment message. The UEtransitions from, for example, an RRC idle state to an RRC connected state by such initial access (random access procedure).

100 200 100 The dedicated BWP is a BWP configured to be dedicated to a certain UE(UE-specific BWP). bwp-id other than “0” may be configured for the dedicated BWP. For example, the dedicated DL BWP and the dedicated UL BWP are configured based on BWP-Downlink and BWP-Uplink which are information elements included in SevingcellConfig in an RRC message which is dedicated signaling transmitted from the base stationto the UE. For example, each of BWP-Downlink and BWP-Uplink may include various parameters (locationAndBandwidth, subcarrierSpacing, and cyclicPrefix) for configuring the BWP.

200 100 200 200 100 200 The base stationcan notify the UEof a BWP (that is, an active BWP) used for communication with the base stationamong the one or more configured BWPs. Specifically, the base stationcan transmit, to the UE, a BWP identifier indicating a BWP to be activated at the time of performing the configuration, that is, a BWP to be first used in communication with the base station. Furthermore, for example, switching by a PDCCH (DCI), RRC signaling, an MAC control element (MAC CE), or a timer is used for control of switching from an active BWP to a BWP that is not an active BWP (hereinafter, referred to as an inactive BWP) and switching from an inactive BWP to an active BWP.

Note that the communication in the active BWP may include at least one of transmission on an uplink-shared channel (UL-SCH) in the BWP, transmission on a random access channel (RACH) in the BWP (when a physical random access channel (Physical RACH: PRACH) occasion is configured), monitoring of a physical downlink control channel (PDCCH) in the BWP, transmission on a physical uplink control channel (PUCCH) in the BWP (when a PUCCH resource is configured), a report of channel state information (CSI) for the BWP, and reception of a downlink-shared channel (DL-SCH) in the BWP.

Here, the UL-SCH is a transport channel and is mapped to a physical uplink shared channel (PUSCH) which is a physical channel. Data transmitted on the UL-SCH is also referred to as UL-SCH data. For example, the data may correspond to UL-SCH data and uplink user data. Further, the DL-SCH is a transport channel and is mapped to a physical downlink shared channel (PDSCH) which is a physical channel. Data transmitted on the DL-SCH is also referred to as DL-SCH data. For example, the data may correspond to DL-SCH data and downlink user data.

The PUCCH is used to transmit uplink control information (UCI). For example, the uplink control information includes a hybrid automatic repeat request (HARQ-ACK), CSI, and/or a scheduling request (SR). The HARQ-ACK includes a positive acknowledgment or a negative acknowledgment. For example, the PUCCH is used to transmit the HARQ-ACK for the PDSCH (that is, the DL-SCH (DL-SCH data and downlink user data)). Here, the DL-SCH data and/or the downlink user data are also referred to as a downlink transport block.

100 100 200 100 200 100 100 For example, the UEmonitors a set of PDCCH candidates in one or a plurality of control resource set(s) (CORESET(s)) in an active DL BWP. Monitoring of the PDCCH may include decoding each of the PDCCH candidates according to a monitored downlink control information (DCI) format. Here, the UEmay monitor a DCI format to which a cyclic redundancy check (also referred to as a CRC parity bit) scrambled by a radio network temporary identifier (RNTI) configured by the base stationis added. Here, the RNTI may include a System Information-RNTI (SI-RNTI), a Random Access RNTI (RA-RNTI), a Temporary C-RNTI (TC-RNTI), a Paging RNTI (P-RNTI), and/or a Cell-RNTI (C-RNTI). The set of PDCCH candidates monitored by the UEmay be defined as a PDCCH search space set. The search space set may include a common search space set(s) (CSS set(s)) and/or a UE specific search space set(s) (USS set(s)). Therefore, the base stationmay set the CORESET and/or the search space set for the UE, and the UEmay monitor the PDCCH in the set CORESET and/or the search space set.

(SSB)

200 The base stationtransmits the SSB in the initial DL BWP. For example, the SSB includes four consecutive OFDM symbols, and a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a PBCH (MIB), and a demodulation reference signal (DMRS) of the PBCH are arranged. A location of a resource element (time resource/frequency resource) to which the SSB is mapped is specified in the 3GPP technical specification, for example, “section 7.4.3.1” of “TS 38.211 v16.2.0” and “section 4.1” of “TS 38.213 v16.2.0”. A bandwidth of the SSB is, for example, a bandwidth of 240 consecutive subcarriers, that is, 20 RBs.

100 The SSB associated with the SIB1 is referred to as a cell-defining SSB (CD-SSB). From the viewpoint of one UE, one serving cell is associated with one CD-SSB. Note that the SIB1 is also referred to as remaining minimum system information (RMSI). One CD-SSB corresponds to one cell having a unique NR cell global identifier (NCGI). The SSB that is not associated with the SIB1 (RMSI) is referred to as a non-cell-defining SSB (Non-CD-SSB).

3 FIG. 200 100 As illustrated in, the base stationnotifies the UEof the SSB being transmitted, for example, by parameters (ssb-PositionsInBurst and ssb-periodicityServingCell) included in ServingCellConfigCommonSIB which is an information element in the SIB1. ssb-PositionsInBurst indicates a time position of the SSB being transmitted in an SS burst of a half frame (5 ms). ssb-periodicityServingCell indicates a transmission period of the SSB.

100 100 100 100 The UEcan grasp an SSB index of the SSB being transmitted based on ssb-PositionsInBurst. Specifically, the maximum quantity (up to 64) of SSBs in the half frame is determined according to the subcarrier spacing and the frequency band, and the UEcan determine a location candidate for the SSB in the time domain based on the SSB index. The UEgrasps whether or not the SSB is actually being transmitted at the location candidate based on ssb-PositionsInBurst. However, the SSB index is not associated with the frequency location in which the corresponding SSB is transmitted. Therefore, in a case where a plurality of SSBs are transmitted in one cell, the UEcannot grasp the frequency location based on the SSB index.

(Separate Initial BWP)

100 100 100 In the 3GPP, assuming the specific UEB (RedCap UE), it is agreed to configure an initial BWP (second initial BWP) for the specific UEB (RedCap UE) independently of the conventional initial BWP. Such a newly introduced initial BWP is referred to as a separate initial BWP. The conventional initial BWP is a first initial BWP assuming the general UE(Non-RedCap UE). The separate initial BWP is the second initial BWP different from the first initial BWP.

100 100 A bandwidth of the separate initial BWP may be equal to or less than the maximum bandwidth of the specific UEB (RedCap UE). A frequency band of the separate initial BWP may be configured in such a way as not to overlap a frequency band of the conventional initial BWP to prevent UL transmission of the general UE(Non-RedCap UE) from being adversely affected.

200 For example, the base stationtransmits a parameter (for example, locationAndBandwidth) indicating the frequency location and/or bandwidth for each of the separate initial DL BWP and/or the separate initial UL BWP by the SIB1. Note that the parameters such as the subcarrier spacing and the cyclic prefix (for example, subcarrierSpacing and cyclicPrefix) for each of the separate initial DL BWP and/or the separate initial UL BWP may be configured or do not have to be configured. CORESET #0 does not have to be configured for the separate initial DL BWP. Further, the SIB1 does not have to be transmitted in the separate initial DL BWP.

4 FIG. In the embodiment, it is assumed that the SSB is transmitted in the separate initial DL BWP.illustrates an example of a relationship between the SSB and the initial BWP.

4 FIG. 200 501 503 502 504 504 503 502 504 100 504 502 In the example illustrated in, the base station(cell) transmits a CD-SSBin a frequency band of a first initial BWPand transmits a Non-CD-SSBin a frequency band of a second initial BWP. The second initial BWPis arranged apart from the first initial BWPin the frequency domain. Since the Non-CD-SSBis transmitted in the second initial BWP, the specific UEB (RedCap UE) can efficiently control communication in the second initial BWPlocated at the same frequency location based on the Non-CD-SSB.

100 501 504 501 504 504 100 504 502 502 504 100 503 504 For example, it is assumed that the specific UEB uses a measurement result for the CD-SSBin initial access with the second initial BWP. In this case, since the frequency band is different between the CD-SSBand the second initial BWP, there is a concern that the measurement result does not align with the actual radio quality of the second initial BWP. On the other hand, in a case where the specific UEB performs initial access with the second initial BWPbased on the measurement result for the Non-CD-SSB, the frequency band of the Non-CD-SSBand the frequency band of the second initial BWPare the same as each other, so that the correct measurement result can be used. In addition, the specific UEB does not need to perform frequency switching (retuning) between the frequency band of the first initial BWPand the frequency band of the second initial BWP.

200 501 503 502 504 As described above, in the embodiment, the base station(cell) transmits the CD-SSBin the first initial BWPwhich is the conventional initial DL BWP, and transmits the Non-CD-SSBin the second initial BWPwhich is the separate initial DL BWP.

100 200 100 Meanwhile, for the UE, a spatial setting is configured from the base stationfor the purpose of the beam control of the PUCCH. Such a spatial setting includes a parameter for configuring a signal to be referred to in the beam control of the PUCCH, and an SSB index can be configured as the parameter. The UEconfigured with the SSB index as the spatial setting for PUCCH transmission performs the PUCCH transmission using the same spatial domain filter as a spatial domain filter used for reception of an SSB indicated by the SSB index.

200 100 100 200 100 Furthermore, a spatial setting is configured from the base stationfor the UEfor the purpose of beam control of a sounding reference signal (SRS) transmitted from the UEto the base station. Such a spatial setting includes a parameter for configuring a signal to be referred to in the beam control of the SRS, and an SSB index can be configured as the parameter. The UEconfigured with the SSB index as the spatial setting for SRS transmission performs the SRS transmission using the same spatial domain filter as a spatial domain filter used for reception of an SSB indicated by the SSB index.

100 200 200 100 In addition, the UEperforms at least one of radio link monitoring (RLM) or beam failure detection (BFD) based on a reference signal received from the base station. The base stationtransmits, to the UE, RLM reference signal configuration information for configuring the reference signal used for at least one of the RLM or the BFD (hereinafter, abbreviated as “RLM/BFD” as appropriate). Such configuration information includes a parameter for configuring a signal to be referred to in the RLM/BFD, and an SSB index can be configured as the parameter.

100 200 200 100 100 In addition, the UEperforms pathloss estimation for uplink transmission power control based on a reference signal received from the base station. The base stationtransmits pathloss reference signal configuration information for configuring the reference signal used for the pathloss estimation to the UE. Such configuration information includes a parameter for configured a signal to be referred to in the pathloss estimation, and an SSB index can be configured as the parameter. The UEconfigured with such an SSB index performs the pathloss estimation (pathloss calculation) by using an SSB indicated by the SSB index.

100 100 502 501 In the existing 3GPP technical specification, in a case where an SSB is used for the beam control of the PUCCH and/or SRS, the SSB index is configured for the UEon the assumption that there is only one SSB in a serving cell. There is no problem if only one SSB is transmitted in the serving cell. However, the UEcannot know which SSB should be used for the beam control of the PUCCH and/or SRS when the Non-CD-SSBis transmitted in the cell in addition to the CD-SSB.

100 502 501 100 Similarly, in the existing 3GPP technical specification, in a case where an SSB is used for the RLM/BFD, an SSB index is configured for the UEon the assumption that there is only one SSB in a serving cell. However, in a case where the Non-CD-SSBis transmitted in the cell in addition to the CD-SSB, the UEcannot know which SSB should be used for the RLM/BFD.

100 502 501 100 Similarly, in the existing 3GPP technical specification, in a case where an SSB is used for the pathloss estimation for uplink transmission power control, an SSB index is configured for the UEon the assumption that there is only one SSB in a serving cell. However, in a case where the Non-CD-SSBis transmitted in the cell in addition to the CD-SSB, the UEcannot know which SSB should be used for the pathloss estimation.

(Configuration of User Equipment)

100 100 100 100 100 110 120 5 FIG. A configuration of the UEaccording to the embodiment will be described with reference to. The UEmay be the general UEA or the specific UEB. The UEincludes a communicatorand a controller.

110 200 200 110 111 112 111 112 The communicatorperforms radio communication with the base stationby transmitting and receiving a radio signal to and from the base station. The communicatorincludes at least one transmitterand at least one receiver. The transmitterand the receivermay include a plurality of antennas and a radio frequency (RF) circuit. The antenna converts a signal into a radio wave and emits the radio wave into space. Furthermore, the antenna receives a radio wave in space and converts the radio wave into a signal. The RF circuit performs analog processing of a signal transmitted and received via the antenna. The RF circuit may include a high frequency filter, an amplifier, a modulator, a low pass filter, and the like.

120 100 120 200 110 100 120 120 120 120 The controllerperforms various types of control in the UE. The controllercontrols communication with the base stationvia the communicator. The operation of the UEdescribed above and described later may be an operation under the control of the controller. The controllermay include at least one processor capable of executing a program and a memory that stores the program. The processor may execute the program to perform the operation of the controller. The controllermay include a digital signal processor that executes digital processing of a signal transmitted and received via the antenna and the RF circuit. The digital processing includes processing of the protocol stack of the RAN. The memory stores the program executed by the processor, a parameter related to the program, and data related to the program. The memory may include at least one of a read only memory (ROM), an erasable programmable read only memory (EPROM), an electrically erasable programmable read only memory (EEPROM), a random access memory (RAM), or a flash memory. All or part of the memory may be included in the processor.

100 200 100 111 200 112 200 120 112 501 502 100 501 502 502 501 The UEconfigured in this manner receives an SSB transmitted in an initial BWP that is a part of a bandwidth of a cell (serving cell) of the base station. In the UEaccording to the first embodiment, the transmitterperforms PUCCH transmission to the base station. The receiverreceives, from the base station, configuration information including an SSB index indicating the SSB to be referred to for controlling the PUCCH transmission. The controllercontrols the PUCCH transmission with reference to the SSB indicated by the SSB index included in the received configuration information. In the first embodiment, the receiverreceives configuration information further including identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB. As a result, the UEcan specify whether the SSB indicated by the configured SSB index is the CD-SSBor the Non-CD-SSBbased on the identification information. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the PUCCH transmission can be appropriately controlled.

502 120 502 501 120 501 502 501 Such configuration information may be spatial relation configuration information for configuring a spatial setting related to beam control for the PUCCH transmission. In a case where the SSB indicated by the SSB index is specified as the Non-CD-SSB, the controllerperforms control to perform the PUCCH transmission using the same spatial domain filter as a spatial domain filter used for reception of the Non-CD-SSB. On the other hand, in a case where that the SSB indicated by the SSB index is specified as the CD-SSB, the controllerperforms control to perform the PUCCH transmission using the same spatial domain filter as a spatial domain filter used for reception of the CD-SSB. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, it is possible to appropriately perform the beam control for the PUCCH transmission.

100 111 200 112 200 120 112 501 502 100 501 502 502 501 In the UEaccording to the first embodiment, the transmitterperforms SRS transmission to the base station. The receiverreceives, from the base station, configuration information including an SSB index indicating the SSB to be referred to for controlling the SRS transmission. The controllercontrols the SRS transmission with reference to the SSB indicated by the SSB index included in the received configuration information. In the first embodiment, the receiverreceives configuration information further including identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB. As a result, the UEcan specify whether the SSB indicated by the configured SSB index is the CD-SSBor the Non-CD-SSBbased on the identification information. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the SRS transmission can be appropriately controlled.

200 200 100 200 Note that the SRS transmission refers to an operation in which the base stationtransmits an SRS, which is an uplink physical signal for channel estimation used for estimating an uplink channel state, to the base station, and the UEperforms the SRS transmission according to the configuration from the base station. That is, the SRS transmission is an operation for link adaptation of an uplink. The link adaptation adapts, to a channel state, a modulation and coding scheme (MCS) applied to data transmission.

502 120 502 501 120 501 502 501 Such configuration information may be spatial relation configuration information for configuring a spatial setting related to beam control for the SRS transmission. In a case where the SSB indicated by the SSB index is specified as the Non-CD-SSB, the controllerperforms control to perform the SRS transmission using the same spatial domain filter as a spatial domain filter used for reception of the Non-CD-SSB. On the other hand, in a case where that the SSB indicated by the SSB index is specified as the CD-SSB, the controllerperforms control to perform the SRS transmission using the same spatial domain filter as a spatial domain filter used for reception of the CD-SSB. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, it is possible to appropriately perform the beam control for the SRS transmission.

100 112 200 120 112 501 502 100 501 502 502 501 In addition, in the UEaccording to the first embodiment, the receiverreceives configuration information including an SSB index indicating an SSB to be referred to for performing the RLM/BFD from the base station. The controllerperforms the RLM/BFD with reference to the SSB indicated by the SSB index included in the received configuration information. In the first embodiment, the receiverreceives configuration information further including identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB. As a result, the UEcan specify whether the SSB indicated by the configured SSB index is the CD-SSBor the Non-CD-SSBbased on the identification information. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the RLM/BFD can be appropriately controlled.

100 100 100 Note that the RLM/BFD includes, for example, processing of detecting a failure event (for example, out-of-synchronization) by monitoring a reception state of a reference signal in the PHY layer of the UE. The UEcounts failure event notifications from the PHY layer to an MAC layer with a counter, and detects a radio link failure or beam failure when the count value becomes equal to or larger than a specified number of times within a predetermined time. In a case where the SSB index is configured in the configuration information, the UEperforms the RLM/BFD by using the SSB.

502 120 502 501 120 501 502 501 Such configuration information may be RLM reference signal configuration information for configuring a reference signal used for at least one of the RLM or the BFD. In a case where the SSB indicated by the SSB index is specified as the Non-CD-SSB, the controllerperforms the RLM/BFD using the Non-CD-SSB. On the other hand, in a case where the SSB indicated by the SSB index is specified as the CD-SSB, the controllerperforms the RLM/BFD using the CD-SSB. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the RLM/BFD can be appropriately controlled.

100 112 200 120 112 501 502 100 501 502 502 501 In addition, in the UEaccording to the first embodiment, the receiverreceives, from the base station, configuration information including an SSB index indicating an SSB to be referred to for the pathloss estimation for the uplink (UL) transmission power control. The controllerperforms the pathloss estimation with reference to the SSB indicated by the SSB index included in the configuration information. In the first embodiment, the receiverreceives configuration information further including identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB. As a result, the UEcan specify whether the SSB indicated by the configured SSB index is the CD-SSBor the Non-CD-SSBbased on the identification information. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the pathloss estimation can be appropriately controlled.

502 120 502 501 120 501 502 501 Such configuration information may be pathloss reference signal configuration information for configuring a reference signal used for the pathloss estimation. In a case where the SSB indicated by the SSB index is specified as the Non-CD-SSB, the controllerperforms the pathloss estimation using the Non-CD-SSB. On the other hand, in a case where the SSB indicated by the SSB index is specified as the CD-SSB, the controllerperforms the pathloss estimation using the CD-SSB. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the pathloss estimation can be appropriately controlled.

501 503 502 504 503 502 504 100 504 502 Here, the CD-SSBmay be an SSB transmitted in the first initial BWP(that is, the conventional initial DL BWP) of the cell (serving cell). The Non-CD-SSBmay be an SSB transmitted in the second initial BWP(that is, the separate initial DL BWP) different from the first initial BWPin the cell (serving cell). Since the Non-CD-SSBis transmitted in the second initial BWPin this manner, the UEcan efficiently control communication in the second initial BWPat the same frequency location based on the Non-CD-SSB.

503 100 504 100 100 100 504 502 The first initial BWPmay be an initial BWP for the general UEA (that is, Non-RedCap UE). The second initial BWPmay be an initial BWP for the specific UEB (that is, RedCap UE) having a lower communication capability than that of the general UEA. As a result, the specific UEB (RedCap UE) can efficiently control communication in the second initial BWPat the same frequency location based on the Non-CD-SSB.

100 In the first embodiment, the identification information may be frequency information indicating the frequency location at which the SSB indicated by the SSB index is transmitted. The frequency information may be a frequency identifier, for example, an absolute radio-frequency channel number (ARFCN). The frequency information may be an RB number indicating a radio resource location in the frequency domain. As a result, the UEcan grasp the frequency location at which the SSB indicated by the SSB index is transmitted based on the frequency information as the identification information, and can appropriately receive the SSB indicated by the SSB index.

501 502 In the first embodiment, the identification information may be a BWP identifier (bwp-id) indicating a downlink BWP in which the SSB indicated by the SSB index is transmitted. In a case where it is assumed that a BWP in which the CD-SSBis transmitted and a BWP in which the Non-CD-SSBis transmitted are necessarily different, the BWP identifier is suitable as the identification information. The BWP identifier can be configured with a smaller amount of information (that is, a short bit length) than the above-described information indicating the frequency location.

501 502 100 502 502 501 502 In the first embodiment, the identification information may be an SSB type identifier indicating one of the CD-SSBand the Non-CD-SSBas a type of the SSB indicated by the SSB index. In a case where it is assumed that information necessary for the UEto receive the Non-CD-SSB, such as a frequency at which the Non-CD-SSBis transmitted, is separately configured, the SSB type identifier is suitable as the identification information. The SSB type identifier may be, for example, 1-bit flag information such as “0” in the case of the CD-SSBand “1” in the case of the Non-CD-SSB. As a result, the identification information can be configured with a small amount of information.

(Configuration of Base Station)

200 200 210 220 230 6 FIG. A configuration of the base stationaccording to the embodiment will be described with reference to. The base stationincludes a communicator, a network interface, and a controller.

210 100 100 210 211 212 211 212 For example, the communicatorreceives a radio signal from the UEand transmits a radio signal to the UE. The communicatorincludes at least one transmitterand at least one receiver. The transmitterand the receivermay include an RF circuit. The RF circuit performs analog processing of a signal transmitted and received via the antenna. The RF circuit may include a high frequency filter, an amplifier, a modulator, a low pass filter, and the like.

220 220 220 300 300 The network interfacetransmits and receives a signal to and from a network. The network interfacereceives, for example, a signal from a neighboring base station connected via an Xn interface, which is an interface between base stations, and transmits the signal to the neighboring base station. In addition, the network interfacereceives, for example, a signal from the core network apparatusconnected via the NG interface, and transmits the signal to the core network apparatus.

230 200 230 100 210 230 300 220 200 230 230 230 230 The controllerperforms various types of control in the base station. The controllercontrols, for example, communication with the UEvia the communicator. Furthermore, the controllercontrols, for example, communication with a node (for example, the neighboring base station and the core network apparatus) via the network interface. The operation of the base stationdescribed above and described later may be an operation under the control of the controller. The controllermay include at least one processor capable of executing a program and a memory that stores the program. The processor may execute the program to perform the operation of the controller. The controllermay include a digital signal processor that executes digital processing of a signal transmitted and received via an antenna and an RF circuit. The digital processing includes processing of the protocol stack of the RAN. The memory stores the program executed by the processor, a parameter related to the program, and data related to the program. All or part of the memory may be included in the processor.

200 100 211 212 100 211 100 100 501 502 502 501 100 The base stationaccording to the first embodiment manages a cell (serving cell) in which the UEexists. The transmittertransmits an SSB in an initial BWP. The receiverreceives a PUCCH (UCI) from the UEexisting in the cell (serving cell). In the first embodiment, the transmittertransmits, to the UE, configuration information including an SSB index indicating the SSB that is referred to by the UEto control the PUCCH transmission and identification information for identifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB. Accordingly, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the UEcan appropriately control the PUCCH transmission.

200 212 100 211 100 100 501 502 502 501 100 In the base stationaccording to the first embodiment, the receiverreceives an SRS from the UEexisting in the cell (serving cell). The transmittertransmits, to the UE, configuration information including an SSB index indicating an SSB that is referred to by the UEto control the SRS transmission, and identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB. Accordingly, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the UEcan appropriately control the SRS transmission.

200 111 100 100 501 502 502 501 100 In the base stationaccording to the first embodiment, the transmittertransmits, to the UE, configuration information including an SSB index indicating an SSB referred to by the UEto perform the RLM/BFD. The configuration information further includes identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB. As a result, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the UEcan appropriately perform the RLM/BFD.

200 211 100 100 501 502 502 501 100 In addition, in the base stationaccording to the first embodiment, the transmittertransmits, to the UE, configuration information including an SSB index indicating an SSB that is referred to by the UEin order to perform the pathloss estimation for the uplink transmission power control. The configuration information further includes identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB. As a result, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the UEcan appropriately perform the pathloss estimation for the uplink transmission power control.

(Operation Example According to First Embodiment)

1 100 100 7 FIG. Next, an operation of the mobile communication systemaccording to the first embodiment will be described. First, an example of an SSB specifying operation in the UEaccording to the first embodiment will be described with reference to. In the operation, the UEmay be in the RRC connected state.

11 112 200 200 100 In step S, the receiverreceives configuration information including an SSB index and identification information from the base station. The configuration information may be transmitted from the base stationto the UEby UE-dedicated signaling, for example, an RRC message such as an RRC reconfiguration message.

12 120 11 502 In step S, the controllerdetermines whether or not the identification information received in step Scorresponds to the Non-CD-SSB.

11 502 12 13 120 11 In a case where the identification information received in step Scorresponds to the Non-CD-SSB(step S: YES), in step S, the controllerspecifies that the SSB index received in step Sis the SSB index of the Non-CD-SSB.

11 501 12 14 120 11 501 In a case where the identification information received in step Scorresponds to the CD-SSB(step S: NO), in step S, the controllerspecifies that the SSB index received in step Sis the SSB index of the CD-SSB.

200 120 501 502 Note that, in a case where a plurality of pieces of configuration information each including an SSB index is configured from the base station, the controllermay specify, for each piece of configuration information, whether the SSB index is the SSB index of the CD-SSBor the SSB index of the Non-CD-SSBbased on identification information corresponding to the SSB index.

(1) Beam Control for PUCCH Transmission

8 FIG. Next, an example of the beam control for the PUCCH transmission according to the first embodiment will be described with reference to.

101 200 100 100 In step S, the base stationtransmits, to the UE, the spatial relation configuration information (PUCCH-SpatialRelationInfo) for configuring the spatial setting related to the beam control for the PUCCH transmission. The UEreceives the spatial relation configuration information (PUCCH-SpatialRelationInfo).

501 502 The spatial relation configuration information (PUCCH-SpatialRelationInfo) includes an SSB index indicating an SSB to be referred to for controlling the PUCCH transmission, and identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB.

200 100 200 100 The base stationmay configure a plurality of pieces of spatial relation configuration information (PUCCH-SpatialRelationInfo) for the UE. Each of the plurality of pieces of spatial relation configuration information (PUCCH-SpatialRelationInfo) may include a combination of the SSB index and the identification information. The base stationmay transmit a PUCCH spatial relation activation/deactivation MAC CE to the UE, thereby activating/deactivating the spatial relation configuration information (PUCCH-SpatialRelationInfo).

102 100 501 502 101 In step S, the UEspecifies whether the SSB index corresponding to the identification information is the SSB index of the CD-SSBor the SSB index of the Non-CD-SSBbased on the identification information received in step S.

103 100 102 200 In step S, the UEreceives the SSB specified in step Sfrom the base station.

104 100 103 100 100 In step S, the UEperforms the beam control for the PUCCH transmission by using the SSB received in step S. Specifically, the UEconfigured with the SSB index (ssb-Index) as the spatial setting for the PUCCH transmission applies the same spatial domain filter as a spatial domain filter used for reception of the SSB of ssb-Index to the PUCCH transmission. For example, in a case where ssb-Index is configured as the spatial setting for the PUCCH resource and the UEperforms transmission in the PUCCH resource, the same spatial domain filter as the spatial domain filter used for reception of the SSB of ssb-Index is used.

105 100 200 200 In step S, the UEperforms the PUCCH transmission to the base station. The base stationreceives the PUCCH.

1101 9 10 FIGS.and 9 10 FIGS.and An example of spatial relation configuration information (PUCCH-SpatialRelationInfo)according to the first embodiment will be described with reference to. Note thatillustrate a description example in the technical specification (TS 38.331) of the RRC layer of 3GPP.

1101 1102 1101 1101 1103 The spatial relation configuration information (PUCCH-SpatialRelationInfo)may include an identifier (servingCellId)of a serving cell to which the spatial relation configuration information (PUCCH-SpatialRelationInfo)is applied. The spatial relation configuration information (PUCCH-SpatialRelationInfo)may include an SSB index (ssb-Index)as a setting of a reference signal (referenceSignal).

1101 1103 1104 1105 1106 1107 502 The spatial relation configuration information (PUCCH-SpatialRelationInfo)includes, as identification information associated with the SSB index (ssb-Index), at least one of frequency information (ssbFrequency-r17), an SSB subcarrier spacing (ssbSubcarrierSpacing-r17), a BWP identifier (ssb-DL-BWP-r17), or an SSB type identifier (ssb-Type-r17). Here, “-r17” means an information element introduced in Release 17 of the 3GPP technical specification, but may also be an information element introduced in Release 18 or later. A condition (Cond) in which such identification information is mandatorily provided may be a condition (NCD-SSB) in which the Non-CD-SSBis transmitted in the separate initial DL BWP configured for the RedCap UE.

(2) Beam Control for SRS Transmission

11 FIG. Next, an example of the beam control for the SRS transmission according to the first embodiment will be described with reference to.

201 200 100 100 In step S, the base stationtransmits, to the UE, the spatial relation configuration information (SRS-SpatialRelationInfo) for configuring the spatial setting related to the beam control for the SRS transmission. The UEreceives the spatial relation configuration information (SRS-SpatialRelationInfo).

501 502 The spatial relation configuration information (SRS-SpatialRelationInfo) includes an SSB index indicating an SSB to be referred to for controlling the SRS transmission, and identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB.

202 100 501 502 201 In step S, the UEspecifies whether the SSB index corresponding to the identification information is the SSB index of the CD-SSBor the SSB index of the Non-CD-SSBbased on the identification information received in step S.

203 100 202 200 In step S, the UEreceives the SSB specified in step Sfrom the base station.

204 100 203 100 100 In step S, the UEperforms the beam control for the SRS transmission by using the SSB received in step S. Specifically, the UEconfigured with the SSB index (ssb-Index) as the spatial setting for the SRS transmission applies the same spatial domain filter as a spatial domain filter used for reception of the SSB of ssb-Index to the SRS transmission. For example, in a case where ssb-Index is configured as the spatial setting for the SRS resource and the UEperforms transmission in the SRS resource, the same spatial domain filter as the spatial domain filter used for reception of the SSB of ssb-Index is used.

205 100 200 200 In step S, the UEperforms the SRS transmission to the base station. The base stationreceives the SRS.

12 13 FIGS.and 12 13 FIGS.and An example of spatial relation configuration information (SRS-SpatialRelationInfo) according to the first embodiment will be described with reference to. Note thatillustrate a description example in the technical specification (TS 38.331) of the RRC layer of 3GPP.

1201 1201 1202 1201 1201 1203 Spatial relation configuration information (SRS-SpatialRelationInfo)is included in an SRS configuration (SRS-Config). The spatial relation configuration information (SRS-SpatialRelationInfo)may include an identifier (servingCellId)of a serving cell to which the spatial relation configuration information (SRS-SpatialRelationInfo)is applied. The spatial relation configuration information (SRS-SpatialRelationInfo)may include an SSB index (ssb-Index)as a setting of a reference signal (referenceSignal).

1204 1205 1206 1207 1203 502 At least one of frequency information (ssbFrequency-r17), an SSB subcarrier spacing (ssbSubcarrierSpacing-r17), a BWP identifier (ssb-DL-BWP-r17), or an SSB type identifier (ssb-Type-r17)is provided as identification information associated with the SSB index (ssb-Index). A condition (Cond) in which such identification information is mandatorily provided may be a condition (NCD-SSB) in which the Non-CD-SSBis transmitted in the separate initial DL BWP configured for the RedCap UE.

(3) RLM/BFD Control

14 FIG. Next, an example of the RLM/BFD control according to the first embodiment will be described with reference to.

301 200 100 100 In step S, the base stationtransmits the RLM reference signal configuration information (RadioLinkMonitoringRS) for configuring the reference signal used for the RLM/BFD to the UE. The UEreceives the RLM reference signal configuration information (RadioLinkMonitoringRS).

501 502 The RLM reference signal configuration information (RadioLinkMonitoringRS) includes an SSB index indicating an SSB to be referred to for performing the RLM/BFD, and identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB.

302 100 501 502 301 In step S, the UEspecifies whether the SSB index corresponding to the identification information is the SSB index of the CD-SSBor the SSB index of the Non-CD-SSBbased on the identification information received in step S.

303 100 302 200 In step S, the UEreceives the SSB specified in step Sfrom the base station.

304 100 303 100 100 100 100 In step S, the UEperforms the RLM/BFD by using the SSB received in step S. The UEmay perform the RLM on a cell basis. In a case where a radio link failure (RLF) is detected by the RLM, the UEmay perform processing for recovery from the RLF. The UEmay perform the BFD on a beam basis in a cell. In a case where a beam failure is detected by the BFD, the UEmay perform processing for recovery from the beam failure.

15 16 FIGS.and 15 16 FIGS.and An example of the RLM reference signal configuration information (RadioLinkMonitoringRS) according to the first embodiment will be described with reference to. Note thatillustrate a description example in the technical specification (TS 38.331) of the RRC layer of 3GPP.

1301 1301 1302 RLM reference signal configuration information (RadioLinkMonitoringRS)can configure any one of the BFD (beamFailure) and the RLM (rlf), or both (both) of the BFD (beamFailure) and the RLM (rlf) as a purpose of a corresponding reference signal, that is, a detection target. The RLM reference signal configuration information (RadioLinkMonitoringRS)may include an SSB index (ssb-Index)as a setting of a detection resource (detectionResource).

1303 1304 1305 1306 1302 502 At least one of frequency information (ssbFrequency-r17), an SSB subcarrier spacing (ssbSubcarrierSpacing-r17), a BWP identifier (ssb-DL-BWP-r 17), or an SSB type identifier (ssb-Type-r17)is provided as identification information associated with the SSB index (ssb-Index). A condition (Cond) in which such identification information is mandatorily provided may be a condition (NCD-SSB) in which the Non-CD-SSBis transmitted in the separate initial DL BWP configured for the RedCap UE.

(4) UL Transmission Power Control

17 FIG. Next, an example of the UL transmission power control according to the first embodiment will be described with reference to.

401 200 100 100 In step S, the base stationtransmits the pathloss reference signal configuration information for configuring the reference signal used for the pathloss estimation for the UL transmission power control to the UE. The UEreceives the pathloss reference signal configuration information. A target of the UL transmission power control is at least one of a PUCCH, a PUSCH, or a service request indicator (SRI)-PUSCH.

501 502 The pathloss reference signal configuration information includes an SSB index indicating an SSB to be referred to for the pathloss estimation, and identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB.

402 100 501 502 401 In step S, the UEspecifies whether the SSB index corresponding to the identification information is the SSB index of the CD-SSBor the SSB index of the Non-CD-SSBbased on the identification information received in step S.

403 100 402 200 In step S, the UEreceives the SSB specified in step Sfrom the base station.

404 100 403 100 200 403 100 200 In step S, the UEperforms the pathloss estimation by using the SSB received in step S. For example, the UEmeasures received power of the SSB received from the base stationin step S, and estimates a pathloss by subtracting the received power from transmission power of the SSB. Note that the UEcan grasp the transmission power of the SSB from, for example, SSB transmission power information (ss-PBCH-BlockPower) transmitted from the base stationin the system information.

405 100 404 In step S, the UEdetermines UL transmission power by using the pathloss estimated in step S. A specific example of a calculation formula for determining the UL transmission power is described below.

406 100 200 405 In step S, the UEtransmits an UL signal to the base stationwith the UL transmission power determined in step S. The UL signal is at least one of a PUCCH signal, a PUSCH signal, or an SRI-PUSCH signal.

18 21 FIGS.to 18 21 FIGS.to An example of the pathloss reference signal configuration information according to the first embodiment will be described with reference to. Note thatillustrate a description example in the technical specification (TS 38.331) of the RRC layer of 3GPP.

18 19 FIGS.and 1401 1401 1406 1401 1406 1402 1403 1404 1405 502 illustrate an example of configuration information (PUCCH-PowerControl) for configuring a UE-specific parameter for transmission power control of the PUCCH. The configuration information (PUCCH-PowerControl) includes pathloss reference signal configuration information (PUCCH-PathlossReferenceRS-r17). The pathloss reference signal configuration information (PUCCH-PathlossReferenceRS-r17)includes an SSB index (ssb-Index-r16)in the case of configuring an SSB (ssb-r17) as a reference signal (referenceSignal-r17). The pathloss reference signal configuration information (PUCCH-PathlossReferenceRS-r17)includes, as identification information associated with the SSB index (ssb-Index-r16), at least one of frequency information (ssbFrequency-r17), an SSB subcarrier spacing (ssbSubcarrierSpacing-r17), a BWP identifier (ssb-DL-BWP-r17), or an SSB type identifier (ssb-Type-r17). A condition (Cond) in which such identification information is mandatorily provided may be a condition (NCD-SSB) in which the Non-CD-SSBis transmitted in the separate initial DL BWP configured for the RedCap UE.

20 21 FIGS.and 1501 1501 1506 1501 1506 1502 1503 1504 1505 502 illustrate an example of configuration information (PUSCH-PowerControl) for configuring a UE-specific parameter for transmission power control of the PUSCH. The configuration information (PUSCH-PowerControl) includes pathloss reference signal configuration information (PUSCH-PathlossReferenceRS-r17). The pathloss reference signal configuration information (PUSCH-PathlossReferenceRS-r17)includes an SSB index (ssb-Index-r16)in the case of configuring an SSB (ssb-r17) as a reference signal (referenceSignal-r17). The pathloss reference signal configuration information (PUSCH-PathlossReferenceRS-r17)includes, as identification information associated with the SSB index (ssb-Index-r 16), at least one of frequency information (ssbFrequency-r17), an SSB subcarrier spacing (ssbSubcarrierSpacing-r17), a BWP identifier (ssb-DL-BWP-r17), or an SSB type identifier (ssb-Type-r17). A condition (Cond) in which such identification information is mandatorily provided may be a condition (NCD-SSB) in which the Non-CD-SSBis transmitted in the separate initial DL BWP configured for the RedCap UE.

A second embodiment will be described mainly with respect to differences from the first embodiment described above.

100 501 502 200 100 501 502 In the first embodiment described above, an example has been described in which the UEspecifies whether an SSB indicated by an SSB index is the CD-SSBor the Non-CD-SSBbased on identification information from the base station. On the other hand, in the second embodiment, a UEautonomously specifies whether an SSB indicated by an SSB index is a CD-SSBor a Non-CD-SSBeven in a case where such identification information (for example, identification information included in spatial relation configuration information (PUCCH-SpatialRelationInfo), identification information included in spatial relation configuration information (SRS-SpatialRelationInfo), identification information included in RLM reference signal configuration information (RadioLinkMonitoringRS), or identification information included in pathloss reference signal configuration information) is not received.

100 111 200 112 200 120 120 502 100 100 100 100 501 502 502 501 In the UEaccording to the second embodiment, a transmitterperforms PUCCH transmission to a base station. The receiverreceives, from the base station, configuration information including an SSB index indicating the SSB to be referred to for controlling the PUCCH transmission. The controllercontrols the PUCCH transmission with reference to the SSB indicated by the SSB index included in the received configuration information. In the second embodiment, the controllerspecifies that the SSB indicated by the SSB index is the Non-CD-SSBin a case where the UEis a specific UEB having a lower communication capability than a general UEA and a predetermined condition is satisfied. That is, the UEautonomously specifies whether the SSB indicated by the configured SSB index is the CD-SSBor the Non-CD-SSB. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the PUCCH transmission can be appropriately controlled.

503 100 504 100 502 504 502 504 100 100 502 100 100 502 502 100 100 502 The predetermined condition is a condition that a first initial BWPfor the general UEA and a second initial BWPfor the specific UEB are configured in the cell (serving cell), and the Non-CD-SSBis transmitted in the second initial BWP. That is, in a case where the Non-CD-SSBis transmitted in the second initial BWP, the UE(the specific UEB) specifies that the SSB indicated by the configured SSB index is the Non-CD-SSB. Note that the UE(the specific UEB) may grasp whether or not the Non-CD-SSBis being transmitted by monitoring (searching) the Non-CD-SSBin the cell (serving cell). The UE(specific UEB) may grasp whether or not the Non-CD-SSBis being transmitted based on system information of the cell (serving cell).

100 100 120 100 501 504 502 100 501 In a case where the UEis the specific UEB and the predetermined condition is not satisfied, the controllerof the UEmay specify that the SSB indicated by the configured SSB index is the CD-SSB. For example, in a case where the second initial BWPis not configured and/or a case where the Non-CD-SSBis not being transmitted in the cell (serving cell), the UEmay specify that the SSB indicated by the configured SSB index is the CD-SSB.

100 111 200 112 200 120 120 502 100 100 100 100 501 502 502 501 In the UEaccording to the second embodiment, the transmitterperforms SRS transmission to the base station. The receiverreceives, from the base station, configuration information including an SSB index indicating the SSB to be referred to for controlling the SRS transmission. The controllercontrols the SRS transmission with reference to the SSB indicated by the SSB index included in the received configuration information. In the second embodiment, the controllerspecifies that the SSB indicated by the SSB index is the Non-CD-SSBin a case where the UEis a specific UEB having a lower communication capability than a general UEA and a predetermined condition is satisfied. That is, the UEautonomously specifies whether the SSB indicated by the configured SSB index is the CD-SSBor the Non-CD-SSB. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the SRS transmission can be appropriately controlled.

100 112 200 120 120 502 100 100 100 100 501 502 502 501 In addition, in the UEaccording to the second embodiment, the receiverreceives configuration information including an SSB index indicating an SSB to be referred to for performing RLM/BFD from the base station. The controllerperforms the RLM/BFD with reference to the SSB indicated by the SSB index included in the received configuration information. In the second embodiment, the controllerspecifies that the SSB indicated by the SSB index is the Non-CD-SSBin a case where the UEis a specific UEB having a lower communication capability than a general UEA and a predetermined condition is satisfied. That is, the UEautonomously specifies whether the SSB indicated by the configured SSB index is the CD-SSBor the Non-CD-SSB. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the RLM/BFD can be appropriately controlled.

100 112 200 120 120 502 100 100 100 100 501 502 502 501 In the UEaccording to the second embodiment, the receiverreceives, from the base station, configuration information including an SSB index indicating an SSB to be referred to for pathloss estimation for uplink transmission power control. The controllerperforms the pathloss estimation with reference to the SSB indicated by the SSB index included in the received configuration information. In the second embodiment, the controllerspecifies that the SSB indicated by the SSB index is the Non-CD-SSBin a case where the UEis a specific UEB having a lower communication capability than a general UEA and a predetermined condition is satisfied. That is, the UEautonomously specifies whether the SSB indicated by the configured SSB index is the CD-SSBor the Non-CD-SSB. Therefore, even in a case where the Non-CD-SSBis transmitted in the cell (serving cell) in addition to the CD-SSB, the pathloss estimation can be appropriately controlled.

(Operation Example According to Second Embodiment)

1 100 100 100 100 22 FIG. Next, an operation of a mobile communication systemaccording to the second embodiment will be described. First, an example of an SSB specifying operation in the UEaccording to the second embodiment will be described with reference to. Here, it is assumed that the UEis the specific UEB. In the operation, the UEmay be in the RRC connected state.

21 112 200 200 100 In step S, the receiverreceives configuration information including an SSB index and identification information from the base station. The configuration information may be transmitted from the base stationto the UEby UE-dedicated signaling, for example, an RRC message such as an RRC reconfiguration message.

22 120 503 100 504 100 502 504 In step S, the controllerdetermines whether or not a predetermined condition is satisfied. The predetermined condition is a condition that the first initial BWPfor the general UEA and the second initial BWP(separate initial DL BWP) for the specific UEB are configured in the serving cell, and the Non-CD-SSBis transmitted in the second initial BWP.

22 23 120 21 In a case where it is determined that the predetermined condition is satisfied (step S: YES), in step S, the controllerspecifies that the SSB index received in step Sis the SSB index of the Non-CD-SSB.

22 24 120 21 501 In a case where it is determined that the predetermined condition is not satisfied (step S: NO), in step S, the controllerspecifies that the SSB index received in step Sis the SSB index of the CD-SSB.

200 120 501 502 Note that, in a case where a plurality of pieces of configuration information each including an SSB index is configured from the base station, the controllermay specify, for each piece of configuration information, whether the SSB index is the SSB index of the CD-SSBor the SSB index of the Non-CD-SSBbased on whether or not the predetermined condition is satisfied.

(1) Beam Control for PUCCH Transmission

23 FIG. Next, an example of beam control for the PUCCH transmission according to the second embodiment will be described with reference to.

111 200 100 100 In step S, the base stationtransmits, to the UE, the spatial relation configuration information (PUCCH-SpatialRelationInfo) for configuring a spatial setting related to the beam control for the PUCCH transmission. The UEreceives the spatial relation configuration information (PUCCH-SpatialRelationInfo).

501 502 The spatial relation configuration information (PUCCH-SpatialRelationInfo) includes an SSB index indicating an SSB to be referred to for controlling the PUCCH transmission. In the second embodiment, the spatial relation configuration information (PUCCH-SpatialRelationInfo) does not have to include identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB.

200 100 200 100 The base stationmay configure a plurality of pieces of spatial relation configuration information (PUCCH-SpatialRelationInfo) for the UE. Each of the plurality of pieces of spatial relation configuration information (PUCCH-SpatialRelationInfo) may include a combination of the SSB index and the identification information. The base stationmay transmit a PUCCH spatial relation activation/deactivation MAC CE to the UE, thereby activating/deactivating the spatial relation configuration information (PUCCH-SpatialRelationInfo).

112 100 501 502 In step S, the UEautonomously specifies whether the configured SSB index is the SSB index of the CD-SSBor the SSB index of the Non-CD-SSBbased on whether or not the predetermined condition is satisfied.

103 100 112 200 In step S, the UEreceives the SSB specified in step Sfrom the base station.

104 100 103 100 100 In step S, the UEperforms the beam control for the PUCCH transmission by using the SSB received in step S. Specifically, the UEconfigured with the SSB index (ssb-Index) as the spatial setting for the PUCCH transmission applies the same spatial domain filter as a spatial domain filter used for reception of the SSB of ssb-Index to the PUCCH transmission. For example, in a case where ssb-Index is configured as the spatial setting for the PUCCH resource and the UEperforms transmission in the PUCCH resource, the same spatial domain filter as the spatial domain filter used for reception of the SSB of ssb-Index is used.

105 100 200 200 In step S, the UEperforms the PUCCH transmission to the base station. The base stationreceives the PUCCH.

(2) Beam Control for SRS Transmission

24 FIG. Next, an example of beam control for the SRS transmission according to the second embodiment will be described with reference to.

211 200 100 100 In step S, the base stationtransmits, to the UE, the spatial relation configuration information (SRS-SpatialRelationInfo) for configuring a spatial setting related to the beam control for the SRS transmission. The UEreceives the spatial relation configuration information (SRS-SpatialRelationInfo).

501 502 The spatial relation configuration information (SRS-SpatialRelationInfo) includes an SSB index indicating an SSB to be referred to for controlling the SRS transmission. In the second embodiment, the spatial relation configuration information (SRS-SpatialRelationInfo) does not have to include identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB.

212 100 501 502 In step S, the UEautonomously specifies whether the configured SSB index is the SSB index of the CD-SSBor the SSB index of the Non-CD-SSBbased on whether or not the predetermined condition is satisfied.

203 100 212 200 In step S, the UEreceives the SSB specified in step Sfrom the base station.

204 100 203 100 100 In step S, the UEperforms the beam control for the SRS transmission by using the SSB received in step S. Specifically, the UEconfigured with the SSB index (ssb-Index) as the spatial setting for the SRS transmission applies the same spatial domain filter as a spatial domain filter used for reception of the SSB of ssb-Index to the SRS transmission. For example, in a case where ssb-Index is configured as the spatial setting for the SRS resource and the UEperforms transmission in the SRS resource, the same spatial domain filter as the spatial domain filter used for reception of the SSB of ssb-Index is used.

205 100 200 200 In step S, the UEperforms the SRS transmission to the base station. The base stationreceives the SRS.

(3) RLM/BFD Control

25 FIG. Next, an example of the RLM/BFD control according to the second embodiment will be described with reference to.

311 200 100 100 In step S, the base stationtransmits the RLM reference signal configuration information (RadioLinkMonitoringRS) for configuring a reference signal used for the RLM/BFD to the UE. The UEreceives the RLM reference signal configuration information (RadioLinkMonitoringRS).

501 502 The RLM reference signal configuration information (RadioLinkMonitoringRS) includes an SSB index indicating an SSB to be referred to for performing the RLM/BFD. In the second embodiment, the RLM reference signal configuration information (RadioLinkMonitoringRS) does not have to include identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB.

312 100 501 502 In step S, the UEautonomously specifies whether the configured SSB index is the SSB index of the CD-SSBor the SSB index of the Non-CD-SSBbased on whether or not the predetermined condition is satisfied.

303 100 312 200 In step S, the UEreceives the SSB specified in step Sfrom the base station.

304 100 303 100 100 100 100 In step S, the UEperforms the RLM/BFD by using the SSB received in step S. The UEmay perform the RLM on a cell basis. In a case where a radio link failure (RLF) is detected by the RLM, the UEmay perform processing for recovery from the RLF. The UEmay perform the BFD on a beam basis in a cell. In a case where a beam failure is detected by the BFD, the UEmay perform processing for recovery from the beam failure.

(4) UL Transmission Power Control

26 FIG. Next, an example of the UL transmission power control according to the second embodiment will be described with reference to.

411 200 100 100 In step S, the base stationtransmits the pathloss reference signal configuration information for configuring a reference signal used for the pathloss estimation for the UL transmission power control to the UE. The UEreceives the pathloss reference signal configuration information. A target of the UL transmission power control is at least one of a PUCCH, a PUSCH, or a service request indicator (SRI)-PUSCH.

501 502 The pathloss reference signal configuration information includes an SSB index indicating an SSB to be referred to for the pathloss estimation. The pathloss reference signal configuration information does not have to include identification information for specifying whether the SSB indicated by the SSB index is the CD-SSBor the Non-CD-SSB.

412 100 501 502 In step S, the UEautonomously specifies whether the configured SSB index is the SSB index of the CD-SSBor the SSB index of the Non-CD-SSBbased on whether or not the predetermined condition is satisfied.

403 100 412 200 In step S, the UEreceives the SSB specified in step Sfrom the base station.

404 100 403 100 200 403 100 200 In step S, the UEperforms the pathloss estimation by using the SSB received in step S. For example, the UEmeasures received power of the SSB received from the base stationin step S, and estimates a pathloss by subtracting the received power from transmission power of the SSB. Note that the UEcan grasp the transmission power of the SSB from, for example, SSB transmission power information (ss-PBCH-BlockPower) transmitted from the base stationin the system information.

405 100 404 In step S, the UEdetermines UL transmission power by using the pathloss estimated in step S.

406 100 200 405 In step S, the UEtransmits an UL signal to the base stationwith the UL transmission power determined in step S. The UL signal is at least one of a PUCCH signal, a PUSCH signal, or an SRI-PUSCH signal.

100 27 32 FIGS.to 27 32 FIGS.to Here, an example of the UL transmission power in the UEaccording to the second embodiment will be described with reference to. Note thatillustrate a description example in the technical specification (TS 38.213) of the PHY layer of 3GPP.

27 FIG. 100 illustrates a calculation formula for determining the PUSCH transmission power. In the calculation formula, the pathloss (PL) is used. For example, the UEperforms transmission power control to increase the PUSCH transmission power as the pathloss increases.

28 FIG. 100 100 501 100 100 504 502 504 502 100 100 100 503 100 502 504 illustrates an operation example of the UE(specific UEB). In step S, the specific UEB (RedCap UE) determines whether or not the predetermined condition is satisfied. Specifically, the specific UEB determines whether or not the second initial BWP(separate initial DL BWP) is configured and the Non-CD-SSBis being transmitted in the second initial BWP. In a case where the predetermined condition is satisfied, in step S, the specific UEB determines whether or not pathloss reference signal configuration information (PUSCH-PathlossReferenceRS) and enableDefaultBeamPL-ForSRS are not provided or whether or not it is before dedicated higher layer parameters are provided to the specific UEB. In a case where the pathloss reference signal configuration information (PUSCH-PathlossReferenceRS) and enableDefaultBeamPL-ForSRS are not provided or it is before the dedicated higher layer parameters are provided to the specific UEB, in step S, the specific UEB calculates the pathloss (PL) by using the Non-CD-SSBtransmitted in the second initial BWP(separate initial DL BWP) and indicated by the SSB index (SS/PBCH block index).

504 502 504 100 504 In a case where the second initial BWP(separate initial DL BWP) is not configured and/or in a case where the Non-CD-SSBis not being transmitted in the second initial BWP, the specific UEB advances the processing to step S.

504 100 100 100 100 In step S, the UEdetermines whether or not the pathloss reference signal configuration information (PUSCH-PathlossReferenceRS) and enableDefaultBeamPL-ForSRS are not provided or whether or not it is before the dedicated higher layer parameters are provided to the UE. In a case where the pathloss reference signal configuration information (PUSCH-PathlossReferenceRS) and enableDefaultBeamPL-ForSRS are not provided or it is before the dedicated higher layer parameters are provided to the UE, the UEcalculates the pathloss (PL) by using the SSB of the SSB index used to acquire an MIB.

29 FIG. 100 illustrates a calculation formula for determining PUCCH transmission power. In the calculation formula, the pathloss (PL) is used. For example, the UEperforms transmission power control to increase the PUCCH transmission power as the pathloss increases.

30 FIG. 100 100 511 100 100 504 502 504 512 100 100 100 513 100 502 504 illustrates an operation example of the UE(mainly, the specific UEB). In step S, the specific UEB (RedCap UE) determines whether or not the predetermined condition is satisfied. Specifically, the specific UEB determines whether or not the second initial BWP(separate initial DL BWP) is configured and the Non-CD-SSBis being transmitted in the second initial BWP. In a case where the predetermined condition is satisfied, in step S, the specific UEB determines whether or not pathloss reference signal configuration information (PathlossReferenceRS) is not provided or whether or not it is before dedicated higher layer parameters are provided to the specific UEB. In a case where the pathloss reference signal configuration information (PathlossReferenceRS) is not provided or it is before the dedicated higher layer parameters are provided to the specific UEB, in step S, the specific UEB calculates the pathloss (PL) by using the Non-CD-SSBtransmitted in the second initial BWP(separate initial DL BWP) and indicated by the SSB index (SS/PBCH block index).

504 502 504 100 514 In a case where the second initial BWP(separate initial DL BWP) is not configured and/or in a case where the Non-CD-SSBis not being transmitted in the second initial BWP, the specific UEB advances the processing to step S.

514 100 100 100 100 In step S, the UEdetermines whether or not the pathloss reference signal configuration information (PathlossReferenceRS) is not provided or whether or not it is before the dedicated higher layer parameters are provided to the UE. In a case where the pathloss reference signal configuration information (PUCCH-PathlossReferenceRS) is not provided or it is before the dedicated higher layer parameters are provided to the UE, the UEcalculates the pathloss (PL) by using the SSB of the SSB index used to acquire the MIB.

31 FIG. 100 illustrates a calculation formula for determining SRS transmission power. In the calculation formula, the pathloss (PL) is used. For example, the UEperforms transmission power control to increase the SRS transmission power as the pathloss increases.

32 FIG. 100 100 521 100 100 504 502 504 522 100 100 100 523 100 502 504 illustrates an operation example of the UE(specific UEB). In step S, the specific UEB (RedCap UE) determines whether or not the predetermined condition is satisfied. Specifically, the specific UEB determines whether or not the second initial BWP(separate initial DL BWP) is configured and the Non-CD-SSBis being transmitted in the second initial BWP. In a case where the predetermined condition is satisfied, in step S, the specific UEB determines whether or not the pathloss reference signal configuration information (PathlossReferenceRS) or SRS-PathlossReferenceRS-Id is not provided or whether or not it is before dedicated higher layer parameters are provided to the specific UEB. In a case where the pathloss reference signal configuration information (PathlossReferenceRS) or SRS-PathlossReferenceRS-Id is not provided or it is before the dedicated higher layer parameters are provided to the specific UEB, in step S, the specific UEB calculates the pathloss (PL) by using the Non-CD-SSBtransmitted in the second initial BWP(separate initial DL BWP) and indicated by the SSB index (SS/PBCH block index).

504 502 504 100 524 In a case where the second initial BWP(separate initial DL BWP) is not configured and/or in a case where the Non-CD-SSBis not being transmitted in the second initial BWP, the specific UEB advances the processing to step S.

524 100 100 100 100 In step S, the UEdetermines whether or not the pathloss reference signal configuration information (PathlossReferenceRS) or SRS-PathlossReferenceRS-Id is not provided or whether or not it is before the dedicated higher layer parameters are provided to the specific UEB. In a case where the pathloss reference signal configuration information (PathlossReferenceRS) or SRS-PathlossReferenceRS-Id is not provided or it is before the dedicated higher layer parameters are provided to the UE, the UEcalculates the pathloss (PL) by using the SSB of the SSB index used to acquire the MIB.

100 200 200 The second embodiment may be used in combination with the first embodiment described above. For example, the UEmay perform the operation according to the second embodiment before receiving the identification information from the base stationand then perform the operation according to the first embodiment after receiving the identification information from the base station.

The operation sequence (and the operation flow) in the above-described embodiment may not necessarily be executed in time series according to the order described in the flow diagram or the sequence diagram. For example, the steps in the operation may be performed in an order different from the order described as the flow diagram or the sequence diagram, or may be performed in parallel. In addition, some of the steps in the operation may be removed and additional steps may be added to the processing. Furthermore, the operation sequence (and the operation flow) in the above-described embodiment may be performed separately and independently, or may be performed by combining two or more operation sequences (and operation flows). For example, some steps of one operation flow may be added to another operation flow, or some steps of one operation flow may be replaced with some steps of another operation flow.

1 1 1 200 100 1 200 In the above-described embodiments, a mobile communication system based on the NR is described as an example of the mobile communication system. However, the mobile communication systemis not limited to this example. The mobile communication systemmay be a system conforming to a TS of any of LTE or another generation system (for example, the sixth generation) of the 3GPP standard. The base stationmay be an eNB that provides evolved universal terrestrial radio access (E-UTRA) user plane and control plane protocol terminations towards the UEin LTE. The mobile communication systemmay be a system conforming to a TS defined in a standard other than the 3GPP standard. The base stationmay be IAB (Integrated Access and Backhaul) or IAB node.

100 200 100 200 100 200 A program for causing a computer to execute each processing performed by the UEor the base stationmay be provided. The program may be recorded on a computer readable medium. The program can be installed in the computer by using the computer readable medium. Here, the computer readable medium on which the program is recorded may be a non-transitory recording medium. The non-transitory recording medium is not particularly limited, but may be, for example, a recording medium such as a CD-ROM (Compact Disk Read Only Memory) or a DVD-ROM (Digital Versatile Disc Read Only Memory). In addition, a circuit that executes each processing performed by the UEor the base stationmay be integrated, and at least a part of the UEor the base stationmay be configured as a semiconductor integrated circuit (chipset, SoC(System On Chip)).

In the above-described embodiment, “transmit (transmit)” may mean to perform processing of at least one layer in a protocol stack used for transmission, or may mean to physically transmit a signal wirelessly or by wire. Alternatively, “transmit” may mean a combination of performing the processing of at least one layer and physically transmitting a signal wirelessly or by wire. Similarly, “receive (receive)” may mean to perform processing of at least one layer in a protocol stack used for reception, or may mean to physically receive a signal wirelessly or by wire. Alternatively, “receive” may mean a combination of performing the processing of at least one layer and physically receiving a signal wirelessly or by wire. Similarly, “acquire (obtain/acquire)” may mean to acquire information from stored information, may mean to acquire information from information received from another node, or may mean to acquire the information by generating information. Similarly, “include (include)” and “comprise (comprise)” do not mean to include only the listed items, but mean that the terms may include only the listed items or may include additional items in addition to the listed items. Similarly, in the present disclosure, “or (or)” does not mean exclusive OR but means OR.

Although the embodiment has been described in detail with reference to the drawings, the specific configuration is not limited to the above description, and various design changes and the like can be made without departing from the gist.

Although the present disclosure has been described in accordance with examples, it is understood that the present disclosure is not limited to the examples and structures. The present disclosure also includes various modifications and modifications within an equivalent range. In addition, various combinations and modes, and other combinations and modes including only one element, more elements, or less elements are also within the scope and idea of the present disclosure.

Features related to the above-described embodiments are additionally described.

100 200 100 112 200 a receiver () configured to receive, from the base station (), configuration information including an SSB index indicating the SSB to be referred to for performing at least one of operations of radio link monitoring (RLM) and beam failure detection (BFD); and 120 a controller () configured to perform the at least one operation with reference to the SSB indicated by the SSB index included in the configuration information, 112 501 502 in which the receiver () is configured to receive the configuration information further including identification information for specifying whether the SSB indicated by the SSB index is a cell-defining SSB () or a non-cell-defining SSB (). A user equipment () that receives a synchronization signal block (synchronization signal/physical broadcast channel (PBCH) block (SSB)) transmitted in an initial bandwidth part (BWP) which is a part of a bandwidth of a cell of a base station (), the user equipment () including:

100 501 503 in which the cell-defining SSB () is an SSB transmitted in a first initial BWP () of the cell, and 502 504 503 the non-cell-defining SSB () is an SSB transmitted in a second initial BWP () different from the first initial BWP () in the cell. The user equipment () according to Supplementary Note 1,

100 503 100 in which the first initial BWP () is an initial BWP for a general user equipment (A), and 504 100 100 the second initial BWP () is an initial BWP for a specific user equipment (B) having a lower communication capability than that of the general user equipment (A). The user equipment () according to Supplementary Note 1 or 2,

100 in which the identification information is information indicating a frequency location at which the SSB indicated by the SSB index is transmitted. The user equipment () according to any one of Supplementary Notes 1 to 3,

100 in which the identification information is a BWP identifier indicating a downlink BWP in which the SSB indicated by the SSB index is transmitted. The user equipment () according to any one of Supplementary Notes 1 to 3,

100 501 502 in which the identification information is an SSB type identifier indicating one of the cell-defining SSB () and the non-cell-defining SSB () as a type of the SSB indicated by the SSB index. The user equipment () according to any one of Supplementary Notes 1 to 3,

100 200 100 112 200 a receiver () configured to receive, from the base station (), configuration information including an SSB index indicating the SSB to be referred to for performing at least one of operations of radio link monitoring (RLM) and beam failure detection (BFD); and 120 a controller () configured to perform the at least one operation with reference to the SSB indicated by the SSB index included in the configuration information, 120 502 100 100 100 in which the controller () is configured to specify that the SSB indicated by the SSB index is a non-cell-defining SSB () in a case where the user equipment () is a specific user equipment (B) having a lower communication capability than that of a general user equipment (A), and a predetermined condition is satisfied. A user equipment () that receives a synchronization signal block (synchronization signal/physical broadcast channel (PBCH) block (SSB)) transmitted in an initial bandwidth part (BWP) which is a part of a bandwidth of a cell of a base station (), the user equipment () including:

100 503 100 504 100 502 504 in which the predetermined condition is a condition that a first initial BWP () for the general user equipment (A) and a second initial BWP () for the specific user equipment (B) are configured in the cell, and the non-cell-defining SSB () is transmitted in the second initial BWP (). The user equipment () according to Supplementary Note 7,

100 120 501 100 100 in which the controller () is configured to specify that the SSB indicated by the SSB index is a cell-defining SSB () in a case where the user equipment () is the specific user equipment (B), and the predetermined condition is not satisfied. The user equipment () according to the Supplementary Note 7 or 8,

100 in which the configuration information includes RLM reference signal configuration information for configuring a reference signal used for at least one of the RLM or the BFD. The user equipment () according to any one of Supplementary Notes 1 to 9,

100 120 502 502 in which the controller () is configured to perform the at least one operation by using the non-cell-defining SSB () in a case where the SSB indicated by the SSB index is specified as the non-cell-defining SSB (). The user equipment () according to any one of Supplementary Notes 1 to 10,

200 200 211 100 a transmitter () configured to transmit, to a user equipment (), a synchronization signal block (synchronization signal/physical broadcast channel (PBCH) block (SSB)) in an initial bandwidth part (BWP) which is a part of a bandwidth of the cell, 111 100 100 in which the transmitter () is configured to further transmit, to the user equipment (), configuration information including an SSB index indicating the SSB to be referred to by the user equipment () to perform at least one of operations of radio link monitoring (RLM) and beam failure detection (BFD), and 501 502 the configuration information further includes identification information for specifying whether the SSB indicated by the SSB index is a cell-defining SSB () or a non-cell-defining SSB (). A base station () that manages a cell, the base station () including:

100 200 301 200 receiving (S), from the base station (), configuration information including an SSB index indicating the SSB to be referred to for performing at least one of operations of radio link monitoring (RLM) and beam failure detection (BFD); and 302 303 304 performing (S, S, and S) the at least one operation with reference to the SSB indicated by the SSB index included in the configuration information, 501 502 in which the receiving includes receiving the configuration information further including identification information for specifying whether the SSB indicated by the SSB index is a cell-defining SSB () or a non-cell-defining SSB (). A communication method executed by a user equipment () that receives a synchronization signal block (synchronization signal/physical broadcast channel (PBCH) block (SSB)) transmitted in an initial bandwidth part (BWP) which is a part of a bandwidth of a cell of a base station (), the communication method including the steps of:

100 200 311 200 receiving (S), from the base station (), configuration information including an SSB index indicating the SSB to be referred to for performing at least one of operations of radio link monitoring (RLM) and beam failure detection (BFD); and 312 303 304 performing (S, S, and S) the at least one operation with reference to the SSB indicated by the SSB index included in the configuration information, 312 502 100 100 100 in which the controlling includes specifying (S) that the SSB indicated by the SSB index is a non-cell-defining SSB () in a case where the user equipment () is a specific user equipment (B) having a lower communication capability than that of a general user equipment (A), and a predetermined condition is satisfied. A communication method executed by a user equipment () that receives a synchronization signal block (synchronization signal/physical broadcast channel (PBCH) block (SSB)) transmitted in an initial bandwidth part (BWP) which is a part of a bandwidth of a cell of a base station (), the communication method including the steps of: